complicated manslaughter case out of Washington state. Gale get. A man was trying to steal his car. Will they find the shooting justified. Dan Abrams after this from Neal Karlinsky. Reporter: It was an otherwise Normal morning when gale georrlack saw his SUV being stolen by Brendan coluzza-graham shown mere on a Facebook page. I just -- a guy just stole my truck. Reporter: The reason Gerlach is on trial and not the car thief is what he failed to mention for another 45 sicks into that 911 call. He'd shot the thief killing him. Okay, where did the vehicle crash? Couple blocks south of my house here. On lee street. I don't know where he went. I don't know if he's still going or what. He leaned back. He pointed at me. I don't know what he pointed about scared me. Reporter: He claimed he fired in self-defense not as a form of Lidge lannty justice. He's not caring about the SUV anymore. He sees something far more important than that. He sees this. Reporter: Prosecutors aren't buying it trying him on manslaughter or killing the suspect with a single shot. This one in a million shot hit its target but could have hit anything else. Not just the shot itself, but the car. Reporter: A key point for prosecutors is that they allege Gerlach couldn't have seen the driver who was unarmed point anything through smoked windows and 60 feet away. You'll see that Mr. Graham was not turned facing Mr Mr. Gerlach as Mr. Gerlach described but was, in fact, shot directly in the back of the head as he was facing forward. Reporter: The question of whether Gerlach feared for his life not just the theft of his car is critical. He pleaded not guilty. If convicted he faces up to ten years in prison. For "Good morning America," Neal Karlinsky, ABC news,seattle. Okay, let's talk about this with ABC's chief legal affairs anchor, Dan Abrams. This is a tricky case. It is because as a legal matter, this self-defense claim is pretty weak, right? The idea the guy is driving away in his car. It's a dirty car, all sorts of stuff in the back of the truck which probably prevented him at least the prosecutors say from actually seeing what the guy was doing was driving the car so the notion they actually saw him turn around point his finger or thinking he had a gun is unlikely. So where does that leave us? It's still a really hard case to get a conviction. So despite the fact that it is a legal matter, the self-defense claim may be weak, the fact that he stole the car and that this guy is shooting after a guy who stole his car in Spokane, Washington, is going to lead it to be tough to get 12 jurors to convict beyond a reasonable doubt. That's why you say it's interesting, in some way the prosecution has already done its most important work. Jury selection, a case where it's all about jury selection. To some degree the evidence is pretty self-explanatory. We know what happened. There's not a lot of debate about what happened apart from whether someone was turning around. The issue here is who is on that jury and prosecutors are going to tell these jurors, you must adhere to the letter of the law and yet what the defense wants is people who are going to say, yeah, you know, I can adhere to the letter of the law but this guy stole his car, you know, so I think it's going to be really hard to have found 12 jurors who are willing to put aside the fact that the car was stolen and just look at this sort of in a vacuum which makes this a much tougher case for prosecutors than might otherwise be. Dan Abrams. Thanks, guys. Now to a story about the

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